In this paper, kriging analysis was applied in predicting and mapping for the contents of Cu, Cr, and Pb in a sampling area of Beijing's eastern farming regions irrigated with wastewater. Based on the kriging interpolation results, the pollution index maps of soil heavy metals were produced and the assessment of pollution was attempted. The results show that 56 of the surface soil of the sampled site was found to have been slightly polluted. The pollution indices of Cu, Cr and Pb were found to be the highest in the northeastern part of the sampling site, followed by the northern part and the southern part in descending order. The variations in pollution may be on account of specific distribution of wastewater outlets and also due to periodical utilization of contaminated sludge in the vegetable garden. Under these circumstances, the crops of the area were yet not substantially affected by these soil pollutants. It appears that immediate soil treatment or any remedial measures may not be necessary. However, it must be taken into account that a further irrigation with wastewater, especially increased utilization of contaminated sludge, could lead to greater accumulation of pollutants in the soil and create health hazards.
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